[jeffreyaven]

Fixes the six open critical Dependabot alerts.

Alert	Package	Where	Fix
#254	zip <= 9.0.4 (zip cloaking, arbitrary file overwrite)	Cargo.lock	0.6.6 -> 9.1.3
#246	proxy-addr < 2.0.8	website/yarn.lock	2.0.8 (within Docusaurus's range)
#242, #241	tinypool < 2.1.2	website/yarn.lock	Yarn resolution ^2.1.2 (2.2.0)
#161	websocket-driver < 0.7.5	website/yarn.lock	0.7.5 (within range)
#140	shell-quote <= 1.8.3	website/yarn.lock	1.12.0 (within range)

Rust (zip)

This picks up the zip part of #63:

• zip 9 needs Rust 1.88, so rust-version goes from 1.75 to 1.88. The crate had not actually built on 1.75 for several releases.
• zip is built with default-features = false, keeping only the pure-Rust deflate backend (deflate-flate2-zlib-rs), so the release targets need no C toolchain. This also drops time 0.3.41 (RUSTSEC-2026-0009), pbkdf2 and base64ct from the lockfile.
• Zip extraction moves into extract_zip. It now fails on symlink entries or entries whose path would leave the destination, where the old code silently skipped unsafe paths. It still writes plain files only, never applying archive permission bits. Three unit tests pin this: a normal archive, a ../ traversal and a symlink.
• bytes and crossbeam-epoch are bumped too, so cargo audit reports no vulnerabilities (only the existing unmaintained/unsound warnings remain).
• New MSRV Check CI job (cargo check --locked --all-targets on 1.88), and .cargo/config.toml with incompatible-rust-versions = "fallback". .cargo/** is added to the CI path filters.
• AGENTS.md and CHANGELOG.md are updated.

Website

Docusaurus 3.9.2 (and 3.10.2) declares tinypool ^1.0.2, and the fix only exists in 2.x, hence the resolution. Docusaurus uses the worker pool only when future.experimental_faster.ssgWorkerThreads is enabled, which this site doesn't do, and tinypool 2.2.0 keeps every option Docusaurus passes to it. The other three were re-resolved within their existing semver ranges.

Verification

• cargo fmt -- --check, cargo clippy --all-targets -- -D warnings, cargo test --lib (106 passed) and cargo test --test '*' all pass; cargo doc --no-deps succeeds.
• cargo +1.88 check --locked --all-targets passes.
• cargo audit: 0 vulnerabilities.
• End to end on Windows x64: stackql-deploy upgrade downloaded stackql_windows_amd64.zip, extracted it with zip 9, and the resulting stackql.exe --version reports v0.12.824. The runtime smoke test on push to main covers extraction on all six targets.
• yarn build of the website succeeds.

Closes #63. It covers the advisories, the MSRV declaration, the MSRV CI job, the resolver config and the extraction tests.